As mobile communication networks evolve and new applications constantly emerge, users form different communication features in different application fields, and different mobile communication types and corresponding user equipment (UE) types are generated, such as machine type communication (MTC), mobile virtual network communication, and public safety communication. From a perspective of a core network (CN) side, different UE types have different communication requirements, such as different optional feature support, service feature requirements, availability requirements, and congestion management mechanisms.
With a sharp increase of a quantity of UE types, an operator proposes a requirement that different dedicated CNs are deployed for the different UE types. The operator subscribes to a dedicated core network type (CN type) for UE types that have a same communication feature, deploys dedicated CN network elements such as a mobility management network element and a data gateway for the UE types, and registers UE that has a same CN type with a CN network element that is dedicatedly deployed for the UE, so that the operator can perform targeted management and maintenance on UE of different types, and implement dedicated use of a dedicated network, thereby improving efficiency of mobile management and session management for access of a huge quantity of UE and reducing network maintenance costs.
After UE is successfully registered with a dedicated network, if the UE is currently in a connected state and leaves a service area of a current dedicated CN network element because of movement, a handover procedure needs to be triggered to hand over the UE to a CN network element in a target cell. According to an operator requirement for dedicated use of a dedicated network, because the UE needs to keep being registered with a dedicated CN of a corresponding CN type as much as possible, the UE should be handed over to a target CN network element of a same CN type to meet an operator requirement for performing dedicated network management on UE of different CN types.
In a research process, it is found that an existing handover procedure cannot ensure that the UE in a connected state is handed over to the target dedicated CN network element of a same CN type as that of the current dedicated CN network element that serves the UE, and the operator requirement for performing dedicated network management on the UE of different CN types cannot be met.